Spinoza breaks with Descartes’ conception of the psychophysical union and deeply changes the ontological statute of men. He considers no longer that human beings in Nature are a dominion within a dominion and share with God the privilege of being substances. In Descartes, the union of an immaterial or non‐extended substance and a material or extended substance remains beyond understanding, since the problem of whether they are able to interact arises. By identifying the mind to the idea (...) of the body, the author of the Ethics provides guidance on how to conceptualize their relationship. The psychophysical parallelism fails to explain both identity and differences in Spinoza. It presupposes homologies and one‐to‐one correspondences between ideas and things, mind and body, and leads to conceptualizing the various modal expressions according to a linearly identical model. The psychophysical union in Spinoza sounds like a duet that puts an end to duality without reducing it to a mechanical identity. (shrink)

By pushing Descartes to more clearly explain the union of body and soul beyond the functioning of a ‘strong’ passion, namely sadness, Elisabeth wants Descartes to review his idea of the passions, and his understanding of the ‘theory of the four humors’. This chapter aims at showing that Descartes turns away from Galen’s theory of the humors, which he globally adopts in the 1633 Treatise of Man. With the shift in his conceptualization of the humors between this Treatise and (...) the Treatise of the Passions (1649), Descartes analyzed more specifically the inner feelings, consciousness, and the passions, by considering that a man is not simply a body, but a psychophysical being, with a body and a soul. (shrink)

Psychophysical scaling models of the form R = f, with R the response and I some intensity of an attribute, all assume that people judge the amounts of an attribute. With simple biases excepted, most also assume that judgments are independent of space, time, and features of the situation other than the one being judged. Many data support these ideas: Magnitude estimations of brightness increase with luminance. Nevertheless, I argue that the general model is wrong. The stabilized retinal image (...) literature shows that nothing is seen if light does not change over time. The classification literature shows that dimensions often combine to produce emergent properties that cannot be described by the elements in the stimulus. These and other effects cannot be adjusted for by simply adding variables to the general model because some factors do not combine linearly. The proposed alternative is that people initially judge the entire stimulus – the object in terms of its environment. This agrees with the constancy literature that shows that objects and their attributes are identified through their relations to other aspects of the scene. That the environment determines judgments is masked in scaling studies where the standard procedure is to hold context constant. In a typical brightness study the essential stimulus might be the intensity of the light or a difference between the light and the background. The two are perfectly confounded. This issue is examined in the case of audition. Judgments of the loudness of a tone depend on how much that tone differs from the previous tone in both pitch and loudness. To judge loudness people first seem to process the stimulus object in terms of differences between it and other aspects in the situation; only then do they assess the feature of interest. Psychophysical judgments will therefore be better interpreted by theories of attention that are based in biology or psychology than those that are based in classical physics. (shrink)

This paper develops a new argument from consciousness to theism: the argument from psychophysical harmony. Roughly, psychophysical harmony consists in the fact that phenomenal states are correlated with physical states and with one another in strikingly fortunate ways. For example, phenomenal states are correlated with behavior and functioning that is justified or rationalized by those very phenomenal states, and phenomenal states are correlated with verbal reports and judgments that are made true by those very phenomenal states. We argue (...) that psychophysical harmony is strong evidence for theism (or, at least, strong evidence against atheism in its standard naturalistic form). (shrink)

An approach to implementing variational Bayesian inference in biological systems is considered, under which the thermodynamic free energy of a system directly encodes its variational free energy. In the case of the brain, this assumption places constraints on the neuronal encoding of generative and recognition densities, in particular requiring a stochastic population code. The resulting relationship between thermodynamic and variational free energies is prefigured in mind–brain identity theses in philosophy and in the Gestalt hypothesis of psychophysical isomorphism.

In past and modern psychophysics there are several unresolved methodological and philosophical problems of human and animal perception, including the outstanding question of the relational basis of whole psychophysics. Here the main issue is discussed: if, and to what extent, there are viable bridges between the traditional “gestalt” oriented approaches and the modern perceptual-cognitive perspectives in psychophysics. Thereby the key concept of psychological “frame of reference” is presented by pointing to Hermann Ebbinghaus' geometric-optical illusions, on the one hand, and Max (...) Wertheimer's treatment of the traditional transposition phenomenon, on the other hand. A much-needed theoretical reorientation of future research may help to overcome the philosophical narrowness of present-day human and comparative psychophysics. (shrink)

In Fechner's psychophysics, the 'mental' and the 'physical' were conceived as two phenomenal domains, connected by functional relations, not as two ontologically different realms. We follow the path from Fechner's foundational ideas and Mach's radical programme of a unitary science to later approaches to primary, psychophysically neutral experience (phenomenology, protophysics). We propose an 'integral psychophysics' as a mathematical study of law-like, invariant structures of primary experience. This approach is illustrated by a reinterpretation of psychophysical experiments in terms of perceptual (...) situations involving a constructed apparatus and an instructed subject. The problematic notion of 'measurement of sensation' is thus eliminated: 'sensations' are merely indices for classes of perceptually equivalent configurations (states of the apparatus) specified by the instruction. The locus of the measured is in the inter-subjectively shared, communicable world—not inside the subject's mind. Finally we discuss the role of integral psychophysics as a scientia prima , logically and methodically preceding physics and psychology. (shrink)

While introspective methods went out of favour with the decline of Titchener’s analytic school, many important questions concern the rehabilitation of introspection in contemporary psychology. Hatfield rightly points out that introspective methods should not be confused with analytic ones, and goes on to describe their “ineliminable role” in perceptual psychology. Here I argue that certain methodological conventions within psychophysics reflect a continued uncertainty over appropriate use of subjects’ perceptual observations and the reliability of their introspective judgements. My first claim is (...) that different psychophysical methods do not rely equally on the introspective capabilities of experimental subjects. I contrast “minimally-introspective” tasks with “introspection-heavy” ones. It is only in the latter, I argue, that introspection can be said to have a non-trivial role in the subjects’ performance. My second claim is that my rough-and-ready distinction maps onto a number of important “dichotomies” in vision science. Not coincidentally, the introspection-heavy categorisation captures many of the tasks typically considered less able to yield useful information regarding the processes underlying visual sensation. (shrink)

The thesis, typical among dualists, that there are no necessitation relations between events of consciousness and physical events implies that it is prima facie lucky that in our world the apparently existing psychophysical laws usually match events of consciousness and physical events in a “harmonious” way. The lucky psychophysical laws argument concludes that typical dualism amounts to a psychophysical parallelism that is prima facie too improbable to be true. I argue that an anthropic reasoning in the space (...) of possible worlds makes the appearance of a harmonious match situation unsurprising, and that this is all that is needed for the argument to be harmless to a typical dualist. (shrink)

Jaegwon Kim and others have claimed that (strong) psychophysical supervenience entails the reducibility of mental properties to physical properties. I argue that this claim is unwarranted with respect to epistemic (explanatory) reducibility (either of a global or of a local sort), as well as with respect to ontological reducibility. I then attempt to show that a robust version of nonreductive materialism (which I call supervenient token-physicalism) can be defended against the charge that nonreductive materialism leads to epiphenomenalism in failing (...) to account for the causal or explanatory relevance of mental properties. (shrink)

We studied two otherwise normal, synaesthetic subjects who `saw' a speci¢c colour every time they saw a speci¢c number or letter. We conducted four experiments in order to show that this was a genuine perceptual experience rather than merely a memory association. (i)The synaesthetically induced colours could lead to perceptual grouping, even though the inducing numerals or letters did not. (ii)Synaesthetically induced colours were not experienced if the graphemes were presented peripherally. (iii)Roman numerals were ine¡ective: the actual number grapheme was (...) required. (iv)If two graphemes were alternated the induced colours were also seen in alternation. However, colours were no longer experienced if the graphemes were alternated at more than 4 Hz. We propose that grapheme colour synaesthesia arises from `cross-wiring' between the `colour centre' (area V4 or V8)and the `number area', both of which lie in the fusiform gyrus. We also suggest a similar explanation for the representation of metaphors in the brain: hence, the higher incidence of synaesthesia among artists and poets. (shrink)

I. The Mind-Body Problem after Kripke This essay will explore an approach to the mind-body problem that is distinct both from dualism and from the sort of conceptual reduction of the mental to the physical that proceeds via causal behaviorist or functionalist analysis of mental concepts. The essential element of the approach is that it takes the subjective phenomenological features of conscious experience to be perfectly real and not reducible to anything else--but nevertheless holds that their systematic relations to neurophysiology (...) are not contingent but necessary. (shrink)

I. The Mind-Body Problem after Kripke This essay will explore an approach to the mind-body problem that is distinct both from dualism and from the sort of conceptual reduction of the mental to the physical that proceeds via causal behaviorist or functionalist analysis of mental concepts. The essential element of the approach is that it takes the subjective phenomenological features of conscious experience to be perfectly real and not reducible to anything else--but nevertheless holds that their systematic relations to neurophysiology (...) are not contingent but necessary. (shrink)

Riemer’s recent paper on the perception of time discusses a neglected yet important topic in the psychological literature: the consequences for psychology (and psychophysics) from the ‘anisotropy’ of time. The paper presents an argument that there are unique kinds of challenges for psychophysics from such temporal anisotropy: (a) Challenges because the psychological experience of time has temporal anisotropy and the physical concept of time does not have temporal anisotropy. (b) Challenges for experimental research which are unique to temporal anisotropy. -/- (...) Although it is important to consider temporal anisotropy, I think there are reasons to deny the force of both kinds of challenges. (shrink)

Psychophysical scales can be constructed under suitable restrictions from appropriate data, but they still do not justify privileged internal sensations.

This chapter identifies, as a key innovative feature of Hellenistic thought about personality, the idea of the person as a psychophysical unit or whole in Stoicism and Epicureanism. It contrasts this idea with the core-centred or part-based view of the personality sometimes found in Plato and Aristotle, while highlighting certain strands in Platonic or Aristotelian thought that may have helped to shape Stoic and Epicurean thought about personality. Psychophysical holism in Stoicism and Epicureanism is illustrated by reference to (...) their views about the physical nature of the psyche and the development of human beings as embodied psychological wholes. Connections are also traced with some puzzles about identity in Stoic and Epicurean thought. (shrink)

Nonreductive physicalists have a causal exclusion problem. Given certain theses all physicalists accept, including psychophysical supervenience and the causal closure of the physical realm, it is difficult to see how irreducible mental phenomena could make a causal difference to the world. The upshot, according to those who push the problem, is that we must embrace reductive physicalism. Only then is mental causation saved. -/- Grant the argument, at least provisionally. Here our focus is the conditional question: What form should (...) one's reductionism take if it is motivated in part by the exclusion problem? Must one be a type identity theorist, or are alternative reductive views available, as Jaegwon Kim has suggested more than once? (shrink)

There are many entry points into the problem of categorization. Two particularly important ones are the so-called top-down and bottom-up approaches. Top-down approaches such as artificial intelligence begin with the symbolic names and descriptions for some categories already given; computer programs are written to manipulate the symbols. Cognitive modeling involves the further assumption that such symbol-interactions resemble the way our brains do categorization. An explicit expectation of the top-down approach is that it will eventually join with the bottom-up approach, which (...) tries to model how the hardware of the brain works: sensory systems, motor systems and neural activity in general. The assumption is that the symbolic cognitive functions will be implemented in brain function and linked to the sense organs and the organs of movement in roughly the way a program is implemented in a computer, with its links to peripheral devices such as transducers and effectors. (shrink)

This paper argues for a physicalistic interpretation of Wittgenstein's Tractatus Logico-Philosophicus. Wittgenstein's general conception of world and language analysis is interpreted and exemplified in relation to the historical background of the psychophysical analysis of sense data and, in particular, color analysis. Three of his main principles of analysis—the principle of independence, the context principle and the principle of atomism—are interpreted and justified on the background of physicalism. From his proof of color exclusion in the Tractatus, it is shown that (...) Wittgenstein had a detailed conception of how philosophy should fulfil the task of distinguishing between sense and nonsense using physicalistic presuppositions. (shrink)

There are two quite distinct ways in which events that we normally think of as “physical” relate in an intimate way to events that we normally think of as “psychological”. One intimate relation occurs in exteroception at the point where events in the world become events as-perceived. The other intimate relationship occurs at the interface of conscious experience with its neural correlates in the brain. The chapter examines each of these relationships and positions them within a dual-aspect, reflexive model of (...) how consciousness relates to the brain and external world. The chapter goes on to provide grounds for viewing mind and nature as fundamentally psychophysical, and examines similar views as well as differences in previously unpublished writings of Wolfgang Pauli, one of the founders of quantum mechanics. (shrink)

What differentiates expressions of pain from other facial expressions? Which facial features convey the most information in an expression of pain? To answer such questions we can explore the expertise of human observers using psychophysical experiments. Techniques such as change detection and visual search can advance our understanding of facial expressions of pain and of evolved mechanisms for detecting these expressions.

People cannot make independent judgements of stimulus attributes and so (Lockhead 1992, p. 551) rather than in terms of stimulus features. The new commentaries here further this statement and also support the observations in the target article that psychophysical scaling methods allow us to measure (1) how context determines judgments and (2) what people remember about prior stimuli.

Psychologically faithful deep neural networks (DNNs) could be constructed by training with psychophysics data. Moreover, conventional DNNs are mostly monocular vision based, whereas the human brain relies mainly on binocular vision. DNNs developed as smaller vision agent networks associated with fundamental and less intelligent visual activities, can be combined to simulate more intelligent visual activities done by the biological brain.